With the development of the times, the types of cooking appliances become more and more diverse. At present, there emerges on the market a novel roasting cooking appliance that may be used for heating papagni type food, sandwiches, etc. A cooking appliance comprises a door and a base. The door is hinged to the base and may be turned up and down. It is used to install many electric devices, such as a microwave generating device, a high-voltage transformer and a fan assembly, within the base of the cooking appliance. At present, the electric devices in the base are mostly directly fixed to the bottom plate of the base, and the weight-bearing design is unreasonable. Additionally, if the cooking appliance falls down during transportation or use, the bottom plate is liable to deform.